Acronym for basic input/output system. On PC-compatible computers, the set of essential software routines that tests hardware at startup, starts the operating system, and supports the transfer of data among hardware devices, including the date and time. The operating system date is initialized from the BIOS or Real Time Clock date when the machine is booted. Many older PCs, particularly those dating before 1997, have BIOSs that store only 2-digit years and thus may have suffered from Year 2000 problems. The BIOS is stored in read-only memory (ROM) so that it can be executed when the computer is turned on. Although critical to performance, the BIOS is usually invisible to computer users. See also AMI BIOS, CMOS setup, Phoenix BIOS, ROM BIOS. Compare Toolbox.
(acronym for basic input/output system) In computing, the part of the operating system that handles input and output. The term is also used to describe the programs stored in ROM (and called ROM BIOS), which are automatically run when a computer is switched on allowing it to boot. BIOS is unaffected by upgrades to the operating system stored on disc.Acronym for basic input/output system. The commands used to tell a CPU how it will communicate with the rest of the computer.

Organic life; constituent of yeast, causing its growth.